LP5036: Clarification on Sequential LED Turn-On Behavior with LP5036EVM

Vedi Govind

Part Number: LP5036
Other Parts Discussed in Thread: USB2ANY, , LP5018

Tool/software:

Hi Team,

I am currently evaluating the LP5036EVM kit using the USB2ANY interface adapter.

While testing the LP5036 LED driver, I observed that when enabling/disabling all 36 individual LEDS, they appear to turn ON/OFF sequentially rather than simultaneously. I would like to confirm whether this is the expected behaviour or if I am missing any settings.

Below are the settings I used to turn the LEDS on and off:

36 Individual LED's ON:

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36 Individual LED's OFF:

{"signature":"oneui-register-data","device":"LP5036","data":[[{"idx":0,"id":"device_config0","value":"0x40"},{"idx":1,"id":"device_config1","value":"0x1C"},{"idx":2,"id":"led_config0","value":"0x0"},{"idx":3,"id":"led_config1","value":"0x0"},{"idx":4,"id":"bank_brightness","value":"0xff"},{"idx":5,"id":"bank_a_color","value":"0x0"},{"idx":6,"id":"bank_b_color","value":"0x0"},{"idx":7,"id":"bank_c_color","value":"0x0"},{"idx":8,"id":"led0_brightness","value":"0xff"},{"idx":9,"id":"led1_brightness","value":"0xff"},{"idx":10,"id":"led2_brightness","value":"0xff"},{"idx":11,"id":"led3_brightness","value":"0xff"},{"idx":12,"id":"led4_brightness","value":"0xff"},{"idx":13,"id":"led5_brightness","value":"0xff"},{"idx":14,"id":"led6_brightness","value":"0xff"},{"idx":15,"id":"led7_brightness","value":"0xff"},{"idx":16,"id":"led8_brightness","value":"0xff"},{"idx":17,"id":"led9_brightness","value":"0xff"},{"idx":18,"id":"led10_brightness","value":"0xff"},{"idx":19,"id":"led11_brightness","value":"0xff"},{"idx":20,"id":"out0_color","value":"0x0"},{"idx":21,"id":"out1_color","value":"0x0"},{"idx":22,"id":"out2_color","value":"0x0"},{"idx":23,"id":"out3_color","value":"0x0"},{"idx":24,"id":"out4_color","value":"0x0"},{"idx":25,"id":"out5_color","value":"0x0"},{"idx":26,"id":"out6_color","value":"0x0"},{"idx":27,"id":"out7_color","value":"0x0"},{"idx":28,"id":"out8_color","value":"0x0"},{"idx":29,"id":"out9_color","value":"0x0"},{"idx":30,"id":"out10_color","value":"0x0"},{"idx":31,"id":"out11_color","value":"0x0"},{"idx":32,"id":"out12_color","value":"0x0"},{"idx":33,"id":"out13_color","value":"0x0"},{"idx":34,"id":"out14_color","value":"0x0"},{"idx":35,"id":"out15_color","value":"0x0"},{"idx":36,"id":"out16_color","value":"0x0"},{"idx":37,"id":"out17_color","value":"0x0"},{"idx":38,"id":"out18_color","value":"0x0"},{"idx":39,"id":"out19_color","value":"0x0"},{"idx":40,"id":"out20_color","value":"0x0"},{"idx":41,"id":"out21_color","value":"0x0"},{"idx":42,"id":"out22_color","value":"0x0"},{"idx":43,"id":"out23_color","value":"0x0"},{"idx":44,"id":"out24_color","value":"0x0"},{"idx":45,"id":"out25_color","value":"0x0"},{"idx":46,"id":"out26_color","value":"0x0"},{"idx":47,"id":"out27_color","value":"0x0"},{"idx":48,"id":"out28_color","value":"0x0"},{"idx":49,"id":"out29_color","value":"0x0"},{"idx":50,"id":"out30_color","value":"0x0"},{"idx":51,"id":"out31_color","value":"0x0"},{"idx":52,"id":"out32_color","value":"0x0"},{"idx":53,"id":"out33_color","value":"0x0"},{"idx":54,"id":"out34_color","value":"0x0"},{"idx":55,"id":"out35_color","value":"0x0"},{"idx":56,"id":"reset","value":"0x0"}]]}

Reference video:

Is this sequential turn-on pattern expected with the current configuration? Or is this because of the LED Driver Response time?

Are there recommended settings or approaches to achieve simultaneous activation of all LEDS?

Looking forward to your guidance.

Regards,
Vedi Govind.

4 months ago

0 Patrick Yao 4 months ago

TI__Mastermind 34630 points

Hi Vedi,

Our expert will give you feedback later.

+1 Felix Wang 4 months ago in reply to Patrick Yao

TI__Expert 5560 points

Hi Vedi,

Yes, the sequential turn-on is expected with the current configuration.

The current individual LED ON and OFF is controlled through writing the corresponding OUTx_Color register as 0xFF and 0x00. For the LP5018, the output state will change immediately once corresponding register value is modified, which should be less than 0.15ms. So the interval during the turn on/off sequence is determined by the I2C communication speed.

If you want to turn on all channels on or off simultaneously, there are 2 methods:

Set or clear the "LED_Global_Off" bit after setting all LEDx_brightness and Outx_color set as 0xFF;
Set the output in bank mode with LED0_BANK_EN to LED11_BANK_EN set as 1b, then set or clear the "Bank_Brightness" as 0xFF or 0x00 after setting Bank_A_Color/Bank_B_Color/Bank_C_Color registers as 0xFF.